Can't tell if it'll damage the tires or just wear them much faster. 5000+ lb truck. 50+ weather. Depends on your speed, vehicle load, and how much turning you'll do.

I had a friend with an e30 325ix with snow tires. In the middle of Seattle summer (75F or so), he took it out to an auto-x* and promptly chunked the tires within 1 minute. So let's say 45 minutes highway driving to the venue, 1 minute of low speed but lots of turns , and pieces of tread were falling off the tires.

One possible alternative (but I have no idea if they are available in the right size) is the Nokian WR or WRG2. These are all season tires (so they can handle summer temps, but won't go quite as low as winters) *and* they are rated for extreme weather conditions (snowflake in the mountain symbol on the sidewall). I have these on a powerful awd sports car, and they rock during the late fall/winter/early spring.

Oh yeah, if you're looking for BMW take-off wheels, you should check out my post in the WTB forum. I found a company in SCal that sold me a pristine set of take-offs for a very good price.

* he was teaching his son to drive, and he wanted a low traction solution so they could do some sliding and learning...